Personally, I use Duplicator (available through Wordpress Plugin Directory), a Wordpress plugin which compresses all the website files, along with a database dump into a ZIP file and creates a PHP file which automates the extraction of that ZIP file, and the reconfiguration of the site to a new domain.
All you do is upload the ZIP and PHP file into an empty folder, access the PHP file through a browser, and follow the bouncing ball. Impossibly simple.
I had done manual migrations, or semi-automated migrations tons of times before I found this plugin. I’d never go back, and can’t think of a reason why I would use anything but Duplicator.